Aquatic birds and selenium in the San Joaquin Valley

Kesterton Reservoir is a series of ponds comprising 1,200 acres sitting in the grasslands of the Kesterton National Wildlife Refuge. It is bounded on the east by the San Luis Drain, a concrete-lined canal that discharges agricultural drainage into the ponds at their southern end, from which point it then flows northward through the twelve ponds (see the map on the page following).

Mike Saki and I studied several of these ponds to determine the concentrations of selenium and other contaminants in food-chain organisms. You'll hear more about this from Mike shortly. My portion of the study was to determine the reproductive success of birds nesting in the ponds and to collect birds so that we could find out what they were eating and what levels of selenium were in their tissues.